1. Field of the Invention
The present invention relates to a portable computer which comprises a keyboard and a coordinate input tablet as data input means.
2. Description of the Related Art
In general, in a so-called lap-top type personal computer or wordprocessor which aims at a compact structure, as shown in FIG. 1, a low-profile flat display unit 3 comprising, e.g., a liquid crystal display (LCD) 1 is coupled to be able to be folded to oppose a keyboard 7 of a main body case unit 5, and to be opened to stand up. With this structure, when a user carries the computer, he or she folds the display unit to make it look like an attache case, and when he uses it, he opens the display unit to watch the screen.
In a conventional portable computer of this type, a keyboard is mainly used for inputting data, such as commands, characters, and the like by a user. For this reason, in order to use the computer, a user must be able to operate the keyboard. However, the user must be accustomed with the keyboard to some extent before he or she can efficiently input data. For this reason, a demand has arisen for an input means which is easier to operate for a user who is not accustomed with the operation of the keyboard.
Under the circumstances, a tablet which can input data using a pen like in handwriting has been developed. FIGS. 2 through 4 show arrangements of portable computers each of which comprises both a tablet and a keyboard.
In the portable computer shown in FIG. 2, a display unit 3 is stored in an upper cover 9, and a keyboard 7 is stored in a main body case 5. The upper cover 9 is coupled to the main body case 5 by hinge portion 11. A tablet 13 is separated from the main body, and is connected to the main body case 5 via a cord 15.
In the portable computer shown in FIG. 3, the tablet 13 is rendered compact, and is assembled in the main body case 5 to be adjacent to the keyboard 7.
In recent years, an integrated display/input device 17 which is integrated by overlaying the transparent tablet 13 on the display unit 3 has been developed as an input means, as shown in FIG. 4. In the integrated display/input device 17, a content displayed on the display unit 3 can be visually observed through the tablet 13, and coordinate data corresponding to a display screen is input by writing on the tablet 13 using a pen in accordance with the displayed content. The coordinate data input from the tablet 13 designates an icon displayed on the display unit 3, and is used as a character pattern. Since the integrated display/input device 17 allows a user to input data as if he or she wrote on paper with a pencil, anyone can easily operate the device 17.
In the portable computer shown in FIG. 4, the integrated display/input device 17 is assembled in the main body case 5, and the keyboard 7 is connected to the integrated display/input device 17 via the cord 15.
However, the portable computer shown in FIG. 2 cannot be rendered compact, and is inconvenient for carrying since the tablet 13 is separated from the main body. Since a data input position is different from a display position, integrated input/display feeling cannot be obtained.
In the portable computer shown in FIG. 3, when the overall computer is rendered compact, the sizes of the tablet 13 and the keyboard 7 become very small. Therefore, the computer shown in FIG. 3 is not easy to use, resulting in poor operability.
Furthermore, the portable computer shown in FIG. 4 cannot be rendered compact since the display unit 3 and the transparent tablet 13 are assembled in the main body case 5, and the keyboard 7 is separated. Therefore, a wide installation area is required in a data input state, and the computer shown in FIG. 4 is inconvenient for carrying. Furthermore, since the display surface (the tablet 13 and the display unit 3) of the integrated display/input device 17 are exposed, the computer must be carefully carried.